Research Fields

Open Position for Research Assistant / PhD Researcher - ref. GASMEMS-ESR2

The GASMEMS
Marie-Curie Initial Training Network
GASMEMS is an international training network for young
researchers in the field of rarefied gas flows in Micro Electro Mechanical Systems (MEMS)
Gas flows in microsystems are of great importance for various applications that touch almost every
industrial field (e.g. fluidic microactuators for active control of aerodynamic flows, vacuum generators
for extracting biological samples, mass flow and temperature micro-sensors, pressure gauges, micro
heat-exchangers for the cooling of electronic components or for chemical applications). The main
characteristic of gas microflows is their rarefaction, which for device design often requires modelling
and simulation both by continuous and molecular approaches. The role played by the interaction
between the gas and the solid device surfaces becomes essential and it is generally not well
understood. Numerous models of boundary conditions have been proposed but they often require an
empirical adjustment strongly dependent on the micro manufacturing technique.
The GASMEMS network has been built from several existing collaborations within bilateral
programmes, from scientific collaborations and national networks with the objectives:
(i) to structure research in Europe in the field of micro gas flows to improve global
fundamental knowledge and enable technological applications to an industrial and
commercial level;
(ii) to train PhD and Post-doctoral researchers at a pan-European level, with the aim of
providing both a global overview on problems linked to gas flows and heat transfer in
microsystems, and advanced skills in specific domains of this research field.
To achieve these objectives, 15 PhD students and 5 Postdoctoral researchers will be recruited in the
framework of this network of 17 European laboratories and industrial partners. Individual career
development plans, mobility, the requirement for every participant researcher to acquire a minimum
knowledge in modelling, simulation, experimental techniques and MEMS manufacturing, in addition
to their project specialisation and Network-wide workshops will ensure that each researcher receives
exposure to, and benefits from, the full expertise of the Network. The involvement of industrial
partners ensures the commercial and industrial relevance of the proposed programme. Coupled with
the broad range of industrial application areas, researchers in this programme will experience
considerably improved career prospects in the various new and emerging applications of gas micro
flows.
More information can be found at http://www.microfluidique.insa-toulouse.fr/gasmems.htm
Research Assistant / PhD Researcher
Ref. N°. GASMEMS-ESR2
Within the GASMEMS Marie-Curie Initial Training Network, a Research Assistant/PhD position is
available on a project entitled:
Dynamics of gas microflows: improvement of analytical and numerical
models at high Knudsen numbers
Duration: 3 years. Expected starting date: January 2009 (by agreement with the researcher)
Application deadline: 15 November 2008
Main goal
Developing effective Direct Simulation Monte Carlo (DSMC) algorithms for simulation of moderateand
high-Knudsen-number gas flows in complex MEMS geometries.
Description of the project
The computational analysis of gaseous flows In MEMS devices operating in flow regimes at larger
Knudsen numbers (Kn > 0.1) cannot be based on classical continuum models of fluid motion
because they are not valid for non-equilibrium flow conditions. In such flows the mean free path of
the gas molecules is comparable to the characteristic size of the micro device and the kinetic effects
of rarefaction and non-equilibrium must be taken into consideration. An appealing aspect of rarefied
flows is that they can be analyzed in detail using the direct simulation Monte Carlo (DSMC) method.
The DSMC technique uses model particles that move and collide in physical space to perform a
direct simulation of the molecular gas dynamics. Intermolecular collisions are modelled using a
statistical approach and this distinguishes the technique from the Molecular Dynamics (MD) method.
Using the DSMC technique, a complete flow field can be modelled at the molecular level. However,
the high computational expense associated with DSMC in concern with microflows simulation has
placed a limit on the size of problem that can be tackled. In this project, the researcher will develop
and implement some modifications and new algorithms of the DSMC code in order to improve its
efficiency for solving GASMEMS problems. The researcher will also work on implementation of more
realistic gas/surface interaction Monte Carlo algorithms. Finally, the researcher will develop a parallel
DSMC code that will be used for simulation of real gas microflows in two- and three- dimensional
domains with complex geometry.
This project is a collaboration between 3 partners: the Institute of Mechanics, Bulgarian Academy of
Sciences, Sofia, Bulgaria, (http://mech.bas.bg), for the numerical modelling of rarefied gas flows and
code DSMC code development; the Advanced Operations and Engineering Group BV (AOES),
Leiden, Netherlands, (http://www.aoes.com), which specialises in development of efficient numerical
techniques and parallel algorithms for the DSMC method, and the Université de Provence
(http://www.univ-provence.fr), Marseille, France, which has an expertise on analytical calculations
and experimental measurement. The researcher will spend the majority of their time at Institute of
Mechanics, Sofia, with an 8-month exchange at AOES, Leiden and 3 months at Université de
Provence, Marseille.
Eligibility
At the time of their appointment, applicants should:
· be in the first 4 years (full-time equivalent) of their research careers, from the date of obtaining
the degree which would formally entitle them to embark on a doctorate;
· be of any nationality, except a national of Bulgaria or the Netherlands. In the case of an
applicant holding more than one nationality (including either Bulgaria or the Netherlands
citizenship), he/she will be eligible if he/she has not resided in Bulgaria or the Netherlands
during the previous 5 years;
· not have resided or carried out his/her main activity in Bulgaria or the Netherlands for more
than 12 months in the 3 years immediately prior to his/her appointment. Short stays such as
holidays are not taken into account;
· if they hold Bulgaria or the Netherlands nationality, be legally resident and have their main
activity in a country not from the EU and not belonging to the list given at ftp://ftp.cordis.europa.eu/pub/fp7/docs/third_country_agreements_en.pdf for at least three of
the last four years immediately prior to their appointment;
· if in doubt about their eligibility for this position, contact Prof. Stefanov, whose contact details
are listed below.
Requirements
This is a challenging and highly rewarding course of study and therefore the successful candidate
should have the following qualifications:
· a first degree in Applied Mathematics, Physics, Computational Science, or Engineering
(preferably a Masters-level degree) with high standard results;
· a good background in fluid mechanics and programming in Fortran and/or C++;
· excellent communication skills and written/verbal knowledge of the English language;
· high autonomy and adaptability skills;
· if the candidate has some experience in microfluidics and/or in experimental techniques adapted
to fluid flows, this would be a benefit.
Financial information / Salary
Annual gross salary: 21,159€ during stays in Bulgaria and France; 34,205€ during stay in
Netherlands
Annual mobility allowance: 3,756€ (for a researcher without family obligations) to 6,010€ (for a
researcher with family obligations) during stays in Bulgaria and France; 6,072€ (for a researcher
without family obligations) to 9,715€ (for a researcher with family obligations) during stays in
Netherlands
Travel allowance: between 250 and 2,500€ per year, depending on the researcher’s country of origin
Career exploratory allowance: a single payment of 2,000€
Contacts
Please contact either of the following for more information about the post or your eligibility to apply for
it:
Prof. Stefan Stefanov: stefanov@imbm.bas.bg or stefanov@mech.bas.bg
Application procedure
Applications for this position, including a Curriculum Vitae or Resume with the contact details of three
referees, a covering letter, attestation of the diploma/master degree and final transcript of academic
records, should be sent via email, using the reference number GASMEMS-ESR2 in the subject line,
to:
Prof. Stefan Stefanov: stefanov@imbm.bas.bg or stefanov@mech.bas.bg
Department of Complex and Multiphase Flows, Institute of Mechanics, BAS, Acad. G. Bonchev Str.,
Block 4, Sofia 1113, Bulgaria
Deadline for applications: 15 November 2008